Understanding particle interactions from a microscopic view of particulate interfaces

Particle interactions are of crucial importance in many applications including fluidized beds and other powder handling systems. The present contribution discusses how surface properties of the particles can be determined in order to get quantitative information on particle interactions. For instance, we apply adsorption experiments in order to get information on dispersive and polar interactions. These measurements are complemented by careful roughness measurements as well as FTIR-spectroscopy and TG-MS analysis. Adhesion force measurements with AFM and ultracentrifuge on well defined ideal as well as heterogeneous surfaces led to the introduction of three generic types of adhesion force distributions: monomodal Weibull, bimodal Weibull and lognormal. The influence of roughness and adsorbed layers on adhesion are shown. In addition, we discuss important aspects of the dynamic nature of the adhesion/detachment process by means of MD-simulations.